Etymology
Advertisement
defensible (adj.)

c. 1300, "ready and able to fight, able to defend," from Old French defensable, from Medieval Latin defensibilis, Late Latin defensibilem, from Latin defens-, past-participle stem of defendere (see defend). Meaning "capable of being defended" is from late 14c., sense of "contributing to defense" is from c. 1400; that of "that may be vindicated" is from early 15c. Related: Defensibility.

Related entries & more 
Advertisement
fencible (adj.)
early 15c., "capable of making a defense," short for defensible; also see fence (n.). As a noun, "soldier enlisted to defend against invasion and not liable to serve abroad" (1796).
Related entries & more 
indefensible (adj.)
1520s, "that cannot be maintained or justified by argument," from in- (1) "not, opposite of" + defensible. From 1560s as "that cannot be maintained by force." Related: Indefensibly.
Related entries & more 
maintainable (adj.)

"capable of being supported or upheld, sustainable, defensible," originally "admissible in law," mid-15c., from maintain + -able. Related: Maintainability.

Related entries & more 
sustainable (adj.)
1610s, "bearable," from sustain + -able. Attested from 1845 in the sense "defensible;" from 1965 with the meaning "capable of being continued at a certain level." Sustainable growth is recorded from 1965. Related: Sustainably.
Related entries & more 
Advertisement
justifiable (adj.)
"capable of being proved just or true, morally defensible," 1520s, from Old French justifiable, from justifiier (see justify). Earlier in same sense was justificable (mid-15c.). Related: Justifiably (mid-15c.).
Related entries & more 
calmative (adj.)
"quieting excessive action," by 1831, from French calmatif; see calm (adj.) + -ative. A Greek-Latin hybrid; purists prefer sedative, but OED writes that "The Latinic suffix is here defensible on the ground of It. and Sp. calmar, F. calmer ...." Also as a noun, "a quieting drug" (1847).
Related entries & more 
crenelate (v.)

"to furnish with a battlement, render defensible," 1823, from crenel + -ate (2). Sometimes also crenellate; the double -l- seems to be from a presumed Latin *crenella as a diminutive of crena. Related: Crenelated, also crenellated; crenelation, crenellation (1849).

The Middle English verb for this was carnel (early 14c.), from the noun in Middle English and from Old French crenelé, from crenel.

Related entries & more 
apologetic (adj.)

1640s, "vindicatory, containing a defense," from French apologétique, from Latin apologeticus, from Greek apologetikos "defensible," from apologeisthai "speak in one's defense," from apologos "an account, story," from apo "away from, off" (see apo-) + logos "speech," from PIE root *leg- (1) "to collect, gather," with derivatives meaning "to speak (to 'pick out words')." Meaning "regretfully acknowledging failure" is by 1836 (apologetic for himself).

Related entries & more 
pile (n.2)

late Old English pil "sharp stake or stick," also, poetically, "arrow, dart," from Latin pilum, the name of the heavy javelin of the Roman foot soldier (source of Old Norse pila, Old High German pfil, German Pfeil "arrow"), a word of uncertain origin. De Vaan finds the identification of it with the pilum that means "pestle, pounder" (from *pis-tlo-, from the root of pinsere "to crush, pound;" see pestle) to be defensible.

In engineering and architecture, "a heavy timber beam, pointed or not, driven into the soil for support of a structure or as part of a wall." It also has meant "pointed head of a staff, pike, arrow, etc." (1590s) and the word is more or less confused with some of the sense under pile (n.1).

Related entries & more